With the proliferation of high quality video, an increasing number of electronics devices (e.g., consumer electronics devices) utilize high-definition (HD) video. Conventionally, most devices compress the HD video, which can be around several Gbps (giga bits per second) in bandwidth, to a fraction of its size to allow for transmission between devices. However, with each compression and subsequent decompression of the video, some video information can be lost and the picture quality is degraded.
In many wireless communication systems, a frame structure is used for data transmission between wireless stations such as a transmitter and a receiver. For example, the IEEE 802.11 standard uses a frame structure in a Media Access Control (MAC) layer and a physical (PHY) layer. In a typical transmitter, a MAC layer receives a MAC Service Data Unit (MSDU) and attaches a MAC header thereto, in order to construct a MAC Protocol Data Unit (MPDU). The MAC header includes information such as a source address (SA) and a destination address (DA). The MPDU is a part of a PHY Service Data Unit (PSDU) and is transferred to a PHY layer in the transmitter to attach a PHY header (i.e., PHY preamble) thereto to construct a PHY Protocol Data Unit (PPDU). The PHY header includes parameters for determining a transmission scheme including a coding/modulation scheme. Before transmission as a packet from a transmitter to a receiver, a preamble is attached to the PPDU, wherein the preamble can include channel estimation and synchronization information.
In such wireless communication systems, before a video stream is transmitted, connection setup and channel bandwidth reservation are conducted. Ideally, sufficient channel bandwidth can be allocated and the video stream can be transmitted smoothly after stream set up control. However, the stream may not receive sufficient channel bandwidth due to other ongoing transmissions on the same channel. In addition, usually the quality of wireless channel is dynamically changed from time to time. Particularly, for 60 GHz wireless channels with beamformed transmissions, the channel can be affected even by human being movement. When the quality of a wireless channel is degraded, usually the MAC/PHY layer automatically changes the modulation and coding scheme (MCS) to a lower level to keep the same BER (bit error rate) performance. The total data throughput is decreased with a lower MCS level. The originally reserved bandwidth for a video stream cannot accommodate the video data due to MCS mode switching to a lower mode.